Charles l



(No Model.)

C. L. BUOKINGHAM. REGULATOR ECR DYNAMC ELECTRIC MACHINES.

No. 320,840. Patented June 23, 1885.

N, PETERS, Pxwwumograpmr; washingnm-D'cf NITED STATES PATENT OFFICEocHAn'Lns L. BUGKINGHAM, or New' Yoan, n. Y.

SPECIFICATION forming part of Letters Patent No. 320,840, dated June23,1885.

Application filed June 9, 1884. (No model.)

To a/ZZ whom it' may concern:

Beit known that I, CHARLES L. BUCKING- HAM, of the city, county, andState of New York, a citizen ofthe United States of America,have made anew and useful Improvement in Regulators for DynamoElectric Machines, ofwhich the following is a speciiication.

My .invention relates to that class of dynamo-regulators bywhich thegenerative capacity of the machine is controlled by short-circuiting orshunting a greater or less amount of current from the field-coils of themachine.

The principal part of my invention c0n sists, first, of adynam0-machine, a regulator therefor for varying the strength of currentin the working-circuit, a motor capable of imparting rotation in eitherdirection for controlling the regulator, and two electro-magnets placedin the working-circuit,and adapted one to control rotation in onedirection and the other to control rotation in thc opposite direction;second, of a dynamo-machine, a variable resistance shunt around theiieldmagnets, a regulator for varying said shuntresistance, and a motoroperated or controlled by the working-circuit capable of imparting-rotation in either direction to said regulator.

My invention comprises a shunt around the field-coils, which includes avariable resistance, such as a pile of` carbon plates, and a novel pressmechanism for subjecting the carbon plates to a greater or less degreeof pressure. In order that the generative capacity of the dynamo-machinemay be increased upon an introduction of additional resistance into theworking-circuit, that the generative capacity may be decreased upon thewithdrawal of resistance from the working-circuit, and that there may benov change in generative capacity while the resistance and currentstrength of the working-circuit remains at or near the normally-requiredamount, I employ a constantly-reciprocating pawl-arm, which engages theratchet teeth of either of two wheels, respectively located on oppositesides of the pawl-arm, according as the main-line current is undulyincreased or weakened, and as it thereby becomes necessary to shunt moreor less current from the field-coils, and which engages the teeth ofneither wheel when the current is near its normal strength. The twowheels gear with a common train, which serves, when the reciprocatingpawl engages one wheel, to turn a screw which compresses the carbonplates, and when it engages the other wheel to turn the screw in theopposite direction and release the pressure upon the carbon pile. Thetwo-and-fro rotation of the press-screw, to govern the strength ofcurrent generated, is controlled by two main-line relays, the armatureof one of which is adj usted to rest at front contact and close a branchor local circuit, while the armature' of the other relay is adjusted torest at back contact and there close a branch or local circuit when thecurrent upon thc working circuit is at its normal strength. Vhen,however, the current is unduly increased, that armature which isnormally at back contact is attracted, thereby breaking its local branchand causing an electro-magnet to so operate as to cause thereciprocating pawl to engage with that ratchet-wheel which serves tocompress the carbon pile. On the other hand, if the current were to beunduly diminished the relay-armature normally on front contact would bereleased, thereby breaking a branch circuit and causing anotherelectro-magnet to so operate as to cause the reciprocating pawl toengage with the other ratchet-wheel and release the pressure upon thepile. By this means it is obvious that there may be any desired changein strength of main-line current before an adjustment is cffccted-thatis, if a normal strength of current is assumed to be ten ampres, thecurrent could be diminished to nine or less, or increased to eleven ormore ampres, without an adjustment taking place; and itis obvious thatan adjustment may be effected by such a uniform and gradual change ofpressure upon the carbon pile as to cause no abrupt current variation.

I will now describe my invention by reference to the accompanyingdrawing.

I? and N are the two poles or branches of the armature of thedynamo-machine. From brush N the conductor ofthe main circuit i11-cludes the coils of the Field-magnets and thence continues by wire 20 topoint 4c, where it divides into two equal branches, which reunite atpoint 9. From point 9 the main conductor includes the coils of relayelectro-magnet aand passes to point l0, there dividing into two equalbranches, which reunite at point l5, and

from the latter point the conductor includes the coils of relayelectro-magnet b and continues on by wire 2l throughout the length ot'the working-circuit back to the positive pole an d brush P of themachine. The two branches of the main conductor terminating at points itand 9, are dillerentially wound upon the core ol" electro-magnet m.Branch 5 8 includes the upper coils ot' m, and is completed throughfront stop,cZ,and armature of relay a. Branch 6 7 includes the lower andoppositely-wound coils of m. In like manner the two branches betweenpoints 10 and 15 are differentially wound upon the cores ofelectro-magnet 11,. Branch 1114S includes the upper coils oi" a, and iscompleted through back contact-point, c, and armature of relayelectro-magnet b. Bran ch l2 13 includes the lower and oppositcly-woundcoils of n. \Vhen the relay-armatures are in the positions shown in thedrawing it is apparent that, however strong the main-line current, itwill divide through the coils cfm and u and produce no magnetic effects;and under such conditions the armature-lever Z, pivoted at p', may be soadjusted by means of springs s and i. as to ass'u me a horizontalposition. The armature of relay a is so adjusted by itsretractingspring0c as, under the influence oi' a normal strength ofcurrent, to rest upon its iront contact, cZ, and close the branchconductor 5 8; but, in the event of any considerable decrease ofcurrent, the armature of a will be released and retracted to its backcontact, c, thereby breaking branch 5 8, and leaving m subject to thesingle branch 6 7. The armature of Z) is so adjusted by itsreti-actingspring y that a normal current will not cause its attraction,and under that condition it will rest on back Contact; but an abnormallystrong current will cause its armature to be attracted to front stop,j", thereby breaking branch 11 14 and leavinga under the inliuenceofbranch l2 13. It is obvious that if ten amepers be considered a normalcurrent, springs a" and 1/ may be so adjusted that the armature of awill not be retracted from its stop until the current has beendiminished to nine or less than nine ampeers, or that the armature of bwill not be attracted from its front stop until the current hasincreased to a strength of eleven ampres or more, or spring x y may beso adjusted that the slightest variation of current strength above orbelow a normal amount will cause one armature to be attracted or theother retracted. Upon a decrease of main-line current, and a retractionol`thc armature oia, electro-magnet m is attracted and slotted arm g/ isthrown to the lei't. On the other hand, upon the attraction ol" armatureof relay b, the armature ol' a is attracted and y/ is movcd to theright. From point 2 and brush N a shuntwire, 7L, connects with theinsulated baseplate Z.: of lhe carbon resistance-pile It; and i'rom theeap-platej of the pile a wire, Zt, connects with thc main conductoratpoint l. The current l'rom brush N may reach pointl ofthe mainconductor by two paths-one through the iield-coils andthe other throughcarbon pile.

An increase or decrease of pressure is applied to the carbon pile by thefollowing c agency: Rotation is imparted to the drivingpulley p by abelt, D, and upon the same shallA with p is a small pulley, 0, which isconnected by a belt-gear with wheel q, iixed to a shalt which carries acrank or eccentric, i', to which is attached a link-arm, s. and at oneend its arm Z is connected to s, while at its other end its arm v isjointed to a reciprocating double pawl-arm, Arm x, atitslower end, has apin which plays in a slot in the vertical arm y. Arm x also slidesbetween two leafsprings, which, when arm y is in a central position,cause arm rc to reciprocate continuously in a middle position withoutengaging the teeth of either wheel XV or Z. Vhen double armature-lever Zis attracted by either m or u, arm i/ pressesx to one side or the other,and causes the reciprocating movement of c to be communicated to wheelsyzu and s, thus giving them a step-by-step movement. If the mainlinecurrent is too strong, arm .r is thrown into engagement with wheel c',and through geartrain (Z cfg the shaft l1., having-a male screw, isturned into the female screw i', so as to give 'i' a longitudinaldownward movementto compress the carbon pile and lower the resistance ofthe shunt around the field-coils. On the contrary, when the main-linecurrent is too weak and pawl-arm a' engages with w, shaft /1y is turnedin an opposite direction, and the pressure from the resistance-pile isremoved. As here shown, pawl-arm .r will be held closely against wheels7 Z, when armature Z is tilted to one side or the other and upon eachbackward movement of the reciprocating pawl to engage a successivetooth, arm Z will be vibrated. In order thatZmaybe comparatively free tovibrate, its armatures must never come in magnetic contact with thecores of m n. These cores must be faced with non-magnetic material, orthere must be limiting-stops provided.

Instead of differential magnets m a ordinary local electro-magnets maybe used whose local circuits may both be normally held open or bothnormally be held closed by relays ab. It is also apparent that a greatvariety of motors may be employed to communicate rotation lrom the shaftoi' the dynamo to thescrewshaft h of the resistance-pile. It will beseen that with the same magnet system a b,instead ot a reciprocating`pawl a constantly-rotating wheel could be employed which would becarried into gear with wheel XV or Z, as occasion required, to eifect ato-and-i'ro rotation. It is also obvious that an electro-magnetic motormay be used to rotate screw-shaft Z1, in one direction or the other bydirecting current to said motor by means ol" relay-magnets e b andproper branch or local circuits.

I am aware that an electro-magnet placed -in the working-circuit forcontrolling the to- 'u is a rock-shaft."

IIO

and-fro rotation of a motor which acts to vary the resistance of a shuntaround the field-magnets of a generator is not new.

That I claim, and desire to secure by Letters Patent, i`s

l. The combination of a normally inactive motor capable of rotation inboth directions to vary the electro motive force of a dyllamo-electricmachine, two main-line electro-magnets, one of whose armature-leversnormally rests upon a front stop and the other upon a back stop, andelectrical contacts, one of which is broken by one electro-magnet uplonan increase of main-line current to cause rotation of said motor in onedirection, and the other of which is broken by a decrease of mainlinecurrent to cause said motor to rotate in the opposite direction.

2. The combination of a dynamo-machine, a shunt-branch around theiield-coils of said dynamo-machine, a variable resistance in said shunt,a motor capable of remaining inactive andof eifecting rotation in eitherdirection for controlling said shunt-resistance, and twoelectro-magnets, one of which is responsive to an increase and the otherto a decrease of current, placed in the working-circuit for controllingthe operation of said motor.

3. rIhe combination of a normally inactive motor capable of effectingrotation in either direction, a dynamo-machine regulator controlled bysaid motor for varying the current strength of the working circuit, twomain-line electro-magnets, one of which is responsive to an increase andthe other to a decrease of current, for controlling the operation ofsaid motor, and a dynamo-electric machine.

4. The combination of a working-circuit, two electro-magnets in saidcircuit respectively responsive to an increase and decrease of currentabove or below a normal strength, whose armatures are so adjusted thatnormally one rests on a front stop and the other on a back stop, and amotor whose rotation in one direction is controlled by one of saidelectromagnets, while the rotation of said motor in the oppositedirection is controlled by the second of said electro-magnets.

5. The combination of a main line,two relaymagnet-s whose armatures areso adj usted that normally one rests on a front stop and the other on aback stop, and a gear-train and a motor which communicates rotation inone direction upon the attraction of that relay-armature which normallyrests on its back stop, and which communicates rotation in an oppositedirection upon the retraction of that relayarmature which normally restsupon its front stop.

6. The combination of a dynamo-machine, a shunt-branch around theeld-coils of the machine, a carbon pile in said shunt, a screwpress forvarying the resistance of said shunt, a motor for rotating the screw ofsaid press in a to-and-fro direction, and two relay-magnets whosearmatures are adj usted, as described, to direct the rotary action ofsaid motor in one direction or the other.

7. In adynamo-machine regulator, the combination of relayelectro-magnets a b, whose armatures are adj usted as described, localbranches which are normally closed by said relay-armatures, one at frontand the other at back contact, differential electro-magnets m n,armature-lever Z, double pawl-arm fr, geared with the shaft of thedynamo-machine, geartrains w c ef g and z d cfg, or their equiva`lents,screws h fi, and carbon pile R.

8. In a dynamo-machine regulator,the combination of relayelectro-magnets a b, whose armatures effect electrical contact, one at afront and the other at a back stop, two

electro-magnets respectively controlled by said relay electro-magnets,armature-bar l, arm y, and double pawl-arm x, and ratchetwheels w z.

9. In a dynamo-machine regnlator,the combination of two differentialelectro-magnets, m n, whose differential coils are normally closed, andtwo relay electro-magnets, a b, for openingand closing branchesembracing coils of said differential electro-magnets,substantially asdescribed.

Signed by me this 31st day of lWIay, 1884:.

CHARLES L. BUGKINGI-IAM.

Vitnesses S. S. WATTERs, J. C. SANDERS.

